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HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query>
    <pages>
      <page pageid="1329" ns="0" title="ARCTech Change Log" contentmodel="wikitext" pagelanguage="en" touched="2010-05-03T17:24:07Z" lastrevid="5215" counter="16150" length="4616" />
      <page pageid="728" ns="0" title="Current events" contentmodel="wikitext" pagelanguage="en" touched="2006-06-18T15:04:43Z" lastrevid="4578" counter="41102" length="2091" />
      <page pageid="739" ns="0" title="Joining" contentmodel="wikitext" pagelanguage="en" touched="2006-06-18T15:04:43Z" lastrevid="5168" counter="56376" length="534" />
      <page pageid="733" ns="0" title="MRC Staff" contentmodel="wikitext" pagelanguage="en" touched="2006-06-18T15:04:43Z" lastrevid="4892" counter="62318" length="8205" />
      <page pageid="742" ns="0" title="Shared Resources" contentmodel="wikitext" pagelanguage="en" touched="2006-06-18T15:04:43Z" lastrevid="3195" counter="24345" length="907" />
      <page pageid="740" ns="0" title="Statistics" contentmodel="wikitext" pagelanguage="en" touched="2006-06-19T09:55:55Z" lastrevid="5200" counter="203792" length="32462" />
      <page pageid="808" ns="2" title="User:Lanji" contentmodel="wikitext" pagelanguage="en" touched="2010-05-03T17:20:57Z" lastrevid="3239" counter="4918" length="259" new="" />
      <page pageid="750" ns="14" title="Category:Campaigns" contentmodel="wikitext" pagelanguage="en" touched="2006-06-21T09:22:02Z" lastrevid="3203" counter="16395" length="2446" />
      <page pageid="865" ns="14" title="Category:GeneralKnowledge" contentmodel="wikitext" pagelanguage="en" touched="2006-06-18T04:30:16Z" lastrevid="5167" counter="70587" length="126" />
      <page pageid="1536" ns="14" title="Category:Units" contentmodel="wikitext" pagelanguage="en" touched="2006-06-18T15:04:43Z" lastrevid="5173" counter="94573" length="2681" />
    </pages>
  </query>
</api>